I have ti046b1 chip (Serial I2C F-RAM) to read.
I tried to read it with my raspberry Pi 3, so I connected SDA SCL VDD GND as shown in pictures, but when I run the command "i2cdetect -y 1" on my Raspberry it shows no device connected to I2C interface (empty) like that:
pi@raspberrypi:~ $ i2cdetect -y 1
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
do you have any idea to solve that ?
I tried by inverting (swiping) SDA SLC connections
I tried by pulling-up to 3.3V SDA and SCL with 10k resistors (as stated here) to end-up with 1.5K pull-up resistance
I checked that there are a built in pull-up 1.8K resistors in the raspberry 3 (see the ohmmeter measure with Pi powerd off of course :) )
I tried to change I2C baudrate by the command:
sudo modprobe -r i2c_bcm2708
sudo modprobe i2c_bcm2708 baudrate=100000
tested with 100KHZ, 200KHZ, 400KHZ, 800KHZ, 1200KHZ (the result is the same
- I have put a scope probes on SCL and SDA when the printer is powered on to see how it negociate (see the piture below)
could you please help me to solve that ?
And to anticipate your first question : I checked all the connections for this wiring :)
scope probes on SCL and SDA when the printer is powered with the chip is inside
Existing pi 3 built-in pull-up 1.8K proven (pi is not powered)